RFR: 8279936: Change shared code to use os:: system API's [v2]

[Harold Seigel]

> Please review this small change to call os:: API's.  the changes were tested with Mach5 tiers 1-2 on Linux, Mac OS, and Windows, and Mach5 tiers 3-5 on Linux x64.  Most of these changes were for I/O related calls.  Changes to memory allocation calls such as malloc and free will be handled in a future change.
> 
> Thanks, Harold

Harold Seigel has updated the pull request incrementally with one additional commit since the last revision:

  restore abort() call

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7055/files
  - new: https://git.openjdk.java.net/jdk/pull/7055/files/ccef3b37..ff0b9192

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7055&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7055&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7055.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7055/head:pull/7055

PR: https://git.openjdk.java.net/jdk/pull/7055